Parallel processing systems of the art have only one processing speed for any particular application running a particular dataset. This is because the number of processing elements that are used to process the application are fixed at compile time. For a parallel processing system whose number of processing elements is not fixed at compile time, but instead can vary at execution time, there remains only one processing element selection criteria—CPU Hours. However, CPU Hours, the amount of time consumed by some number of processing elements, does not give an indication of performance because in order to indicate performance one must be able to predict the performance for some application processing some dataset with some number of processing elements.